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Date: 13 Aug 2006 11:37:53
From: Stan Jensen
Subject: Comet 177P/Barnard Magnitude Descrepancies
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Hey all, have a question for those of you who observe comets.
Comet 177P/Barnard is said to be an 8th magnitude object in Hercules
right now. At least according to Skyhound -
http://www.skyhound.com/sh/comets.html.
But Guide, Starry Night, and The Sky all show it +13th mag., and we've
looked for it the past several nights, and there's no +8th mag. comet
where it's supposed to be.
Anyone got the scoop? Maybe it's a hoax, like the Mars one.:)
S,.
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Date: 13 Aug 2006 13:07:03
From: Greg Crinklaw
Subject: Re: Comet 177P/Barnard Magnitude Descrepancies
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Hi Stan,
Stan Jensen wrote:
> Hey all, have a question for those of you who observe comets.
>
> Comet 177P/Barnard is said to be an 8th magnitude object in Hercules
> right now. At least according to Skyhound -
> http://www.skyhound.com/sh/comets.html.
>
> But Guide, Starry Night, and The Sky all show it +13th mag., and we've
> looked for it the past several nights, and there's no +8th mag. comet
> where it's supposed to be.
That's because those programs rely solely on the magnitude parameters
from the IAU. This comet is a relatively recent discovery and the IAU
is waiting for more data before they compute accurate magnitude
parameters. The magnitude parameters are used by software to predict
the magnitude of a comet.
For my Comet Chasing web site (which you refer to above) I use recent
observations to compute magnitude parameters that will give better
current estimates. I do this for my web site and my SkyTools software.
This is what makes my Comet Chasing web site useful to comet observers.
Recent magnitude estimates for this comet really are 8th magnitude. So
why can't you see it? Because this is a large (12') diffuse comet.
Think of comets like galaxies. Some 11th magnitude galaxies are obvious
in small telescopes. But others, such as IC 10, are more difficult
because their light is spread over a larger area without any brighter
central region. The same holds true for comets.
So my suggestion is to try again. But this time look for a large faint
glow rather than something small and bright. Be sure to use your lowest
magnification eyepiece for this one. Comets like this are often more
easily seen in large binoculars than telescopes.
Clear skies,
Greg
--
Greg Crinklaw
Astronomical Software Developer
Cloudcroft, New Mexico, USA (33N, 106W, 2700m)
SkyTools: http://www.skyhound.com/cs.html
Observing: http://www.skyhound.com/sh/skyhound.html
Comets: http://www.skyhound.com/sh/comets.html
To reply take out your eye
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Date: 13 Aug 2006 23:57:54
From: David Nakamoto
Subject: Re: Comet 177P/Barnard Magnitude Descrepancies
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Greg Crinklaw wrote:
> Hi Stan,
>
> Stan Jensen wrote:
>> Hey all, have a question for those of you who observe comets.
>>
>> Comet 177P/Barnard is said to be an 8th magnitude object in Hercules
>> right now. At least according to Skyhound -
>> http://www.skyhound.com/sh/comets.html.
>>
>> But Guide, Starry Night, and The Sky all show it +13th mag., and we've
>> looked for it the past several nights, and there's no +8th mag. comet
>> where it's supposed to be.
>
> That's because those programs rely solely on the magnitude parameters
> from the IAU. This comet is a relatively recent discovery and the IAU
> is waiting for more data before they compute accurate magnitude
> parameters. The magnitude parameters are used by software to predict
> the magnitude of a comet.
>
> For my Comet Chasing web site (which you refer to above) I use recent
> observations to compute magnitude parameters that will give better
> current estimates. I do this for my web site and my SkyTools software.
> This is what makes my Comet Chasing web site useful to comet observers.
>
> Recent magnitude estimates for this comet really are 8th magnitude. So
> why can't you see it? Because this is a large (12') diffuse comet.
12 arc-minutes across and 8th mag?! This one's gonna be a little hard
to find from suburban locations. Since you equate this with galaxies,
think large faint face-on spiral.
--- Dave
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Date: 14 Aug 2006 08:22:29
From: Stan Jensen
Subject: Re: Comet 177P/Barnard Magnitude Descrepancies
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Hey Greg,
I'm definately going to try again. I haven't been burned really in all
the years of looking for these things. I was just wondering about the
discrepancy in magnitude estimates.
Next clear night I'll be out there. but instead of the 16-inch SCT, I
might try my 4-inch Tak.
S.
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Date: 13 Aug 2006 17:09:40
From: Eugene Griessel
Subject: Re: Comet 177P/Barnard Magnitude Descrepancies
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Stan Jensen <spam@wonderful.spam > wrote:
>Hey all, have a question for those of you who observe comets.
>
>Comet 177P/Barnard is said to be an 8th magnitude object in Hercules
>right now. At least according to Skyhound -
>http://www.skyhound.com/sh/comets.html.
>
>But Guide, Starry Night, and The Sky all show it +13th mag., and we've
>looked for it the past several nights, and there's no +8th mag. comet
>where it's supposed to be.
>
>Anyone got the scoop? Maybe it's a hoax, like the Mars one.:)
I'd place my faith in
http://cfa-www.harvard.edu/iau/Ephemerides/Comets/0177P.html
rather.
Eugene L Griessel
INDECISION is the key to FLEXIBILITY.
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Date: 13 Aug 2006 13:08:56
From: Greg Crinklaw
Subject: Re: Comet 177P/Barnard Magnitude Descrepancies
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Hi,
Eugene Griessel wrote:
> I'd place my faith in
> http://cfa-www.harvard.edu/iau/Ephemerides/Comets/0177P.html
> rather.
For an accurate position, yes. For up to date magnitudes, no.
Greg
--
Greg Crinklaw
Astronomical Software Developer
Cloudcroft, New Mexico, USA (33N, 106W, 2700m)
SkyTools: http://www.skyhound.com/cs.html
Observing: http://www.skyhound.com/sh/skyhound.html
Comets: http://www.skyhound.com/sh/comets.html
To reply take out your eye
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Date: 14 Aug 2006 11:28:29
From: G\Laptop\
Subject: Re: Comet 177P/Barnard Magnitude Descrepancies....FOUND!
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I can verify that there is a comet. Last night at a dark site(6 to 6.5). I
put my GPS Celestron Cassagrain 11"(USing RA/Dec) & a fellow other astr-nut.
Put his Dob 12"(Star Hopped) on it and found it. It was a wide faint smudge
& diffuse. Need a wide field to see it. According to starry night pro 5.1 it
was a mag 9.60. We agreed it was about a 10mag or more. Could be your focal
lenght or you need darker skies...
When does this comet get closer to us? Or is it heading out from us?...
"Stan Jensen" <spam@wonderful.spam > wrote in message
news:qlhud21podbgut23inqk86tsqqiicaa3fc@4ax.com...
> Hey all, have a question for those of you who observe comets.
>
> Comet 177P/Barnard is said to be an 8th magnitude object in Hercules
> right now. At least according to Skyhound -
> http://www.skyhound.com/sh/comets.html.
>
> But Guide, Starry Night, and The Sky all show it +13th mag., and we've
> looked for it the past several nights, and there's no +8th mag. comet
> where it's supposed to be.
>
> Anyone got the scoop? Maybe it's a hoax, like the Mars one.:)
>
> S,.
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